<html>
<head> 
<meta charset="utf-8">
<title>属性选择器</title>
<link href="ys.css" rel="stylesheet" type="text/css">
</head> 
<body>
<form action="#">
  <div><input type="text" /></div>

  <div>
    <input type="submit" value="我要回到上一步" />
    <input type="submit" value="禁止点下一步" disabled />
  </div>
</form> 
</body>
</html>